Surgical retractor extensions

ABSTRACT

A surgical retractor apparatus having one or more independent, removable extension members adapted to be mounted at the distal end of the retractor, or between the blades of a spreadable retractor, after the retractor has been positioned in the patient, such that a significant portion of the extension member extends beyond the distal end of the retractor to preclude or minimize intrusion of tissue into the access area created by the retractor. The extension members may vary in size and shape so that the most appropriate extension member can be chosen to address the intrusion problem, and the extension members may be mounted at various fixed locations, using clips, mechanical interlocking structures or the like.

This application claims the benefit, of U.S. Provisional PatentApplication Ser. No. 60/691,141, filed Jun. 16, 2005, and U.S.Provisional Application Ser. No. ______ filed Dec. 2, 2005, thedisclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates generally to the field of devices utilized insurgery to retract and retain tissue, organs or the like to provide thesurgeon with access or an unobstructed pathway to an organ, bone, tissueor point in the body. Such devices are typically referred to genericallyas retractors. More particularly, the invention relates to retractorsutilized with minimally invasive surgical techniques, wherein minimallysized openings are created in the body rather than relatively largeincisions. Tubular devices known as cannula retractors, or spreadingretractors having finger-like extensions or blades, are inserted intothe small opening and through or around the body tissues, muscles,tendons, ligaments, etc., thereby minimizing damage to the body. Thesurgeon then performs the necessary procedure through the retractor tubeusing specially designed tools and equipment.

A problem with known retractors used in minimally invasive surgery isthat the distal end profile or configuration of the device is fixed. Atypical tubular retractor has a circular or elliptical transversecross-section with the distal end lying in the plane perpendicular orslanted relative to the longitudinal axis. Other tubular distractors mayhave non-planar ends of varying configurations, such as having aspatula-like extension. Spreading retractors likewise have varying endconfigurations. Because the distal end configurations of the devices arefixed, the devices often fail to prevent creep or herniation of tissueat or around the distal end of the device, and this tissue creep caninterfere with the necessary physical or visual access. This isparticularly true when the distal end of the retractor device ispositioned adjacent or near a bone, such as a vertebra for example, thatdoes not have a planar or smooth outer contour, or where the retractordevice is disposed at a non-perpendicular angle to the bone. In thesecircumstances it often becomes necessary for the surgeon to cut away theinterfering tissue, thereby creating additional tissue damage that needsto heal and increasing the possibility of detrimental results such asbleeding, increased pain, infection and the like.

One attempted solution that is found in certain retractors of thespreadable blade type is to provide shim members that are mounted ininterior channels disposed in each of the blades. The shim can beextended beyond the distal end of the blade by sliding the shim relativeto the blade. The shortcomings of this solution to the problem of tissuecreep is that the location of the shims are determined by the locationof the blades after they have been positioned and spread. Thus, thesurgeon cannot address the problem of tissue creep that occurs betweenthe blades.

The invention at hand addresses this tissue creep problem by providing aretractor device for minimally invasive surgery that incorporatesextension members in the form of shields or barriers that areselectively attached at, adjacent or to the end of a tubular retractor,and to the ends or sides of blade-type spreadable retractors, so as toextend therefrom in order to fill any gaps between the distal end orside of the retractor and the bone, organ or other body component ofconcern, such that tissue is precluded from creeping or herniating intothe gap. The extensions may be mounted to the retractor at any pointabout or adjacent the distal end utilizing various mechanical joiningtechniques, and the extensions may vary in shape, size, thickness andother characteristics. The extensions may be preformed with a fixedcurvature so as to match the interior curvature of the retractor, orthey may be composed of a flexible material such that they adapt to theinterior curvature of the retractor upon affixation. The extensions maybe provided with teeth, apertures, slits or the like to better preventtissue creep.

Specialized applicator equipment or tools are preferably provided thatallow the surgeon to grasp or secure a particular extension, to insertthe extension into and down the retractor, and to affix the extension tothe interior wall or distal end of the retractor. Such equipment maytake the form of forceps that retain the extension member duringinsertion and placement within the tubular retractor or other retractorblade.

SUMMARY OF THE INVENTION

The invention is a retractor device for minimally invasive surgery thatincorporates independent, discrete, removable extension members in theform of shields or barriers that are selectively attached at, adjacentor to the end of a tubular retractor, or at, adjacent or to the ends orsides of blade retractors, so as to extend therefrom in order to fillany gaps between the distal end of the retractor and the bone, organ orother body component of concern, such that tissue is precluded fromcreeping or herniating into the gap. The extensions may be mounted tothe retractor at multiple chosen locations utilizing various mechanicalinterlocking, clipping or similar joining techniques, and the extensionsmay vary in shape, size, thickness and other characteristics. Theextensions may be preformed with a fixed curvature so as to match theinterior curvature of the retractor, or they may be composed of aflexible material such that they adapt to the interior curvature of theretractor upon affixation. The extensions may be provided with teeth,apertures, slits or the like to better prevent tissue creep. Theextensions are attached to the retractor after the retractor has beenpositioned in the patient.

In a preferred embodiment, the extension members are clipped to the endor exposed edge of a tubular retractor, or to the ends, sides or exposededges of a blade retractor, using a generally J- or U-shaped clip memberlocated on the extension member. In an alternative embodiment theextension member comprises a compressible slotted annular band wherebythe extension member is retained against the inner wall of the tubularretractor by biasing forces.

Specialized equipment or tools allow the surgeon to grasp or secure oneor more chosen extensions, to insert the extension into and down theretractor, and to affix the extension to the interior wall or distal endof the retractor. In a preferred embodiment, the applicator or insertiontool comprises a forceps-type device having a means to temporarilyretain one or two extension members on a pair of extended L-shaped arms,wherein squeezing a pair of handles results in separation of theL-shaped arms.

It is contemplated that the invention may be provided to surgeons in theform of a kit, such kit comprising a plurality of extension members ofvarying shapes and sizes, an applicator tool, and possibly a depthgauge.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of the invention showing a tubular retractorand an extension member having a mounting post.

FIG. 2 is a perspective view showing the distal end of the tubularretractor with the extension member affixed.

FIG. 3 is a partial cross-sectional view of the distal end of thetubular retractor with a pair of extension members mounted thereto, withone being shown in cross-section.

FIG. 4 is a perspective view of an alternative embodiment of theextension member having a mounting clip.

FIG. 5 is a perspective view of the distal end of an alternativeembodiment tubular retractor having a pair of the extension members ofFIG. 4 mounted thereto.

FIG. 6 is an end view of the distal end of the tubular retractor of FIG.5.

FIG. 7 is a side view of an applicator tool for positioning theexpansion members.

FIG. 8 is a partial view of the end of the applicator tool, having asingle extension member shown in cross-section and retained thereby.

FIG. 9 is a top view showing a pair of extension members positionedwithin a tubular retractor prior to connection to the retractor.

FIG. 10 is a front view of another alternative embodiment of theextension member having a pair of mounting clips, teeth and slots.

FIG. 11 is a side view of another alternative embodiment of theextension member having a grasping protrusion and a lip member.

FIG. 12 is a front view of another alternative embodiment of theextension member having extended lateral members.

FIG. 13 is a view of an alternative embodiment for the tubular retractorhaving a plurality of grid apertures to receive the extension members.

FIG. 14 is a view similar to FIG. 3 of an alternative embodiment for theextension member and mounting means, where a separate U-clip member isemployed.

FIG. 15 is a cross-sectional view of the embodiment of FIG. 13, showingattachment of an extension member and an additional accessory to afenestrated retractor.

FIG. 16 is a perspective view of an alternative embodiment of theextension member, where the extension member is maintained within atubular retractor by friction or biasing forces.

FIG. 17 is a partial cross-sectional view of the extension member ofFIG. 16 shown positioned within a tubular retractor.

FIG. 18 is a top view of the extension member of FIG. 16 shownpositioned within a tubular retractor.

FIG. 19 is a view of an insertion or applicator tool for the extensionmember of FIG. 16.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, the invention will now be described indetail with regard for the best mode and the preferred embodiments. Theinvention is a surgical retractor apparatus or assembly and its methodof use, the surgical retractor assembly having selectable extensionmembers that are mounted or affixed at, on, to or adjacent the distalend of a tubular retractor member, or the ends or sides of a spreadableblade retractor, such that the distal profile or configuration can bealtered to better match the contour of the bone, organ or other bodycomponent or better still the shape of a portion of the open areabetween the distal end of the retractor and the bone, organ or otherbody component, so as to preclude or minimize intrusion of tissue orother matter by creep or herniation into the access passageway definedby the retractor. The extension members are independent, discrete andremovable members, and are attached to the retractor after the retractorhas been inserted into the patient. The illustrations show a tubularretractor member that is circular in transverse cross-section, but it isto be understood that it is contemplated that a tubular retractor ofelliptical or other cross-sectional configuration may also be utilized.Likewise, it is also to be understood that it is contemplated that theretractor may also comprise one of the type having one or morespreadable blades or finger-like sections, each of the blades orsections having a distal end of fixed configuration, in which case theextension members may be positioned on the sides of the blades as wellas on the ends.

The apparatus comprises a retractor member 10 comprising a generallyelongated main body 11 of relatively small transverse dimension having aproximal end 12 and a distal end 13, wherein the distal end 13 isadapted to be inserted into the body through a relatively small incisionor opening, whereby an access pathway is created that enables thesurgeon to visualize and perform procedures in the interior of thepatient. The length of the main body 11 is chosen such that the proximalend 12 remains disposed externally to the body during the procedure. Asshown in FIG. 1, the retractor member 10 may comprise a tubular mainbody 11 that is circular in transverse cross-section, with the distalend 13 and proximal end 12 lying in planes perpendicular to thelongitudinal axis. Alternatively, the main body 11 may be elliptical orotherwise non-circular in cross-section, and the distal end 13 andproximal end 12 may be disposed in non-perpendicular planes or may havenon-planar configurations, such as for example when a spatula-likeconfiguration is provided on the distal end 13.

The extension members 20 are independent, discrete, removable membersdistinct from the retractor member 10 and may be composed of varyingmaterials and comprise a shielding main body 28 having varying shapesand sizes. Preferably, the extension members 20 are relatively thin soas to only minimally diminish the size of the access opening provided bythe retractor member 10. In a preferred embodiment, the extensionmembers 20 are composed of a plastic material such that the main body 28is able to flex so as to conform to the interior curvature of theretractor member 10 when mounted thereon. For example, as shown in FIGS.1 through 5, the extension member main bodies 28 may be relativelyplanar prior to connection to the retractor member 10, becoming curvedupon being forced against the retractor member 10 for attachment.Alternatively, the mains bodies 28 of the extension members 28 may beformed with a relatively rigid central portion 41 acting in the form ofa “backbone”, with relatively flexible lateral portions 42 extending toeither side of the central portion 41, as shown in FIG. 10. The centralportion 41 may be formed as a thicker region, may be composed of adifferent material possessing more rigidity than the material composingthe lateral portions 42, or may comprise ridges or similar reinforcingstructures. Furthermore, the main bodies 28 of the extension members 20may be preformed with a fixed curvature matching that of the interior ofthe retractor member 10. The particular shapes of the extension members20 may vary, such that they may be symmetrical or asymmetrical, therebyallowing a surgeon to choose the shape that best fills the gap betweenthe distal end 13 of the retractor member 10 and the bone, organ or bodycomponent in any given procedure. Examples of differing configurations,not to be taken as limiting, are shown in FIGS. 1, 4, 10, 11 and 12. Thedimensions of the extension members 20 may vary in height or width, suchthat for example one extension member 20 may extend a short distanceaxially but cover a large distance circumferentially, or vice versa. Asshown in FIG. 10, the extension members 20 may be provided with teeth24, slots 25 or other surface or body elements to better secure thetissue at the distal end 13 of the retractor member 10 to prevent creep,herniation or intrusion. As shown in FIG. 11, the extension members 20may be provided with a distal lip member 26 for this same purpose.

Mounting means 30 are provided to affix or attach one or more extensionmembers 20 in a fixed, non-moving, manner at or adjacent the distal end13 of the retractor member 10, while the retractor member 10 ispositioned within the patient, such that the extension members 20 extendbeyond the distal end 13. Multiple extension members 20 may be abuttedor overlapped if necessary. Mounting means 30 may comprise any suitableaffixation mechanism, although a mechanical interlock is preferred overadhesive bonding or the like. One embodiment for mounting means 30 isshown in FIGS. 1 through 3, where mounting means 30 comprises incombination a plurality of mechanical interlocking members comprisingmounting apertures 31 and mounting posts 32, with the apertures 31disposed in the main body 11 near the distal end 13 of retractor member10 and the posts 32 disposed on the exterior side of the extensionmembers 20. To attach the extension member 20 to the retractor member10, the mounting post 32 is pressed into the mounting aperture 31, theelements 32 and 33 being sized such that the post 32 is retained by theaperture 31 by friction or by expansion of a compressed post 32 tocreate a mechanical interlocking. The mounting means 30 should securethe extension member 20 with sufficient retention such that theextension member 20 will not be dislodged during the surgical procedureor upon removal of the retractor member 10.

Alternatively, mounting means 30 may comprise recessed mechanisms,spring-biased mechanisms, clip mechanisms or any other suitable meansfor mounting the extension members 20 to the retractor member 10. Apreferred mounting means 30 comprising one or more generally J- orU-shaped clip or hook members 33 is shown in FIGS. 4 through 12, wherethe clip member 33 is sized and spaced a selected distance from the mainbody 28 of the extension member 20 so as to securely receive the edge ofthe distal end 13 of the retractor member 10, the clip member 33preferably being either biased outwardly when the extension member 20 isbrought upward onto the edge of the distal end 13 of the retractormember 10 or being pulled against the retractor member 10 when theextension member 20 is flexed to adopt the curve of the retractor member10. The provision of plural clip members 33 on a single extension member20, as shown in FIG. 10, acts to prevent undesired pivoting ortranslation of the extension member 20 relative to the retractor tube 10after affixation.

Still another embodiment for the extension member 20 and mounting means30 is shown in FIG. 14, where the extension member 20 is provided with aslot or aperture 36 that receives a separate U-shaped clip member 35that is mounted onto the distal end 13 of the retractor tube 10. Withthis embodiment, as with the embodiment of FIGS. 1 through 3, theextension member 20 can be positioned without first over-advancing theextension member 20 beyond the distal end 13 and then retracting to seatthe clip member 33.

Another embodiment for the extension member 20 is shown in FIG. 12,where the extension member 20 is provided with lateral wing members 27that greatly extend the lateral dimension of the extension member 20.With this configuration it is easy to overlap multiple extension members20. Furthermore, such a configuration is useful for application toretractors of the spreadable blade type, since by their nature axiallyoriented gaps are created between the arms or blades of the retractorwhen such arms are expanded.

Grasping forceps may be utilized to position the extension members 20within the retractors members 10, but preferably specially adaptedextended tools, forceps or similar grasping instruments are provided toattach the extension member 20 to the retractor member 10 after theretractor member 10 has been inserted into the body. A representativeapplicator tool 90 is illustrated in FIGS. 7 through 9, wherein the tool90 is designed such that the extension member 20 is pressed against theinterior wall of the retractor member 10 by squeezing the handles 91,the applicator tool 90 being spring biased so as to remain in the closedposition until force is applied to the handles 91. The handles 91 arepivotally joined by pivot means 92 to L-shaped arm members 93, thelength of the L-shaped arms 93 being greater than the length of theretractor member 10. Extension member retention means 94 are disposedadjacent or near the distal end 96 of the arms 93. The extension memberretention means 94 as shown comprise pin members 95 that are receivedwithin tool apertures 22 disposed in the extension members 20. To applythe extension members 20 of the embodiment shown in FIGS. 1 through 3,one or two extension members 20 are temporarily affixed to the pinmembers 95, the extension member 20 is properly positioned at the distalend 13 of the retractor member 10, and the handles 91 are closed toexpand the L-shaped arms 93, thereby forcing the post member 32 of theextension member 20 into the mounting aperture 31. For the embodiment ofthe extension member 20 shown in FIGS. 4 through 10 and 12, theextension member 20 is inserted through the distal end 13 a sufficientdistance for the clip member 33 to clear the distal end 13, then theextension member 20 is retracted to seat the clip member 33 on thedistal end 13 of the retractor member 10.

Alternatively, the tool connector means 21 of the extension members 20may comprise internally extending grasping projections or nubs 23, asshown in FIG. 11, such that conventional forceps or the like may beutilized to grasp and place the extension member 20. In a differentembodiment, a bayonet-type applicator tool may be utilized to positionthe extension member 20, the bayonet-type applicator tool having anaxially offset handle portion to allow visualization within theretractor member 10.

The embodiments of the extension members shown in FIGS. 4 through 12 andin FIG. 14 are advantageous in that standard retractor members 10currently in production do not need to be altered, since the extensionmembers 20 are clipped onto the distal end 13 of the tubular retractor.For the embodiment shown in FIGS. 1 through 3, the retractor tubes 10must be provided with corresponding apertures 31 to receive theextension member posts 32. This design somewhat limits the location ofthe extension member 20 on the retractor member 10, but the provision ofa relatively large number of apertures 31 addresses this issue. In analternative embodiment of the retractor member 10, as shown in FIG. 13,a fenestrated retractor member 10 comprises a large number of gridapertures 34, which may comprise various shapes, patterns andconcentrations, such that the clip members 33 of the extension members20 can be positioned at multiple locations. The clip members 33 mayextend in any direction, including the distal, proximal or lateraldirections. At least some of the grid apertures 34 are axially spacedalong the retractor member 10, such that the grid apertures 34 are notequidistant from the distal end 13. These grid apertures 34 may extendthe entire length of the retractor member 10. With this configurationthe extension members 20 can be inverted such that the clip members 33extend distally, which may enable better placement of the extensionmembers in certain circumstances, as shown in FIG. 15. Additionally,other accessories 99 such as light sources, scopes, suctions,irrigators, etc. may be mounted into the grid apertures 34 in similarmanner using clip members 98, with the clip members 98 extending in anydirection, including the distal, proximal or lateral directions. Theclip members 98 may be removable attachments to the accessories 99 ormanufactured to be an integral member. Both of these embodiments may beincorporated into either tubular or blade retractors.

Another alternative embodiment for the extension member 20 is shown inFIGS. 16 through 18. In this embodiment, the extension member 20 isretained within the tubular retractor member 10 by frictional or biasingforces. The extension member 20 comprises a shielding main body 28depending from a slotted annular collar or ring member 29. The shape ofthe main body 28 may vary. The collar member 29 is sized such that itsouter diameter matches that of the inner diameter of the tubularretractor member 10 within a small tolerance, such that the extensionmember 20 can be advanced down the interior of the retractor member 20and is retained in the desired location at the distal end 13 byfrictional forces, or preferably is sized and configured such that theends of the slotted collar member 29 must be compressed slightly inorder for the extension member 20 to be inserted into the retractormember 10, whereby biasing forces retain the extension member 20 at thedesired location. The extension member 20 may be shaped much lesscircular than shown in the drawings in the neutral state, depending onthe range of flexation inherent in the material of construction. In thecase of a pure frictional fit, the collar member 29 may be non-slotted,i.e., comprising a full 360 degree circle. An alternative insertion orapplicator tool 90 is shown in FIG. 19, the tool 90 comprising anelongated handle 91 connected to a ram member 97, which is annular asshown but may comprise a cylinder or other shape.

Preferably, the invention is provided as a kit comprising multipleextension members 20 of varying sizes and configurations, along with theapplicator tool 90 and a depth gauge, such that the configuration of thedistal end 13 of any standard retractor member 10 can be reconfigured asneeded to prevent tissue creep.

The methodology of the invention comprises the steps of inserting aretractor member 10 into the body of a patient, this step beingperformed in standard manner. The surgeon then accesses the situation atthe distal end 13 of the retractor member 10 to determine whetherundesirable tissue creep is occurring or is likely to occur during theprocedure. To preclude or minimize such tissue creep, the surgeonselects an appropriately sized and shaped extension member 20, insertsit into interior of the retractor member 10 using an appropriateapplicator or insertion tool 90, and secures it to or adjacent thedistal end 13 of the retractor member 10 in any of the manners discussedabove. If necessary, multiple extension members 20 can be positioned atdifferent points about the distal end 13, with the extension members 20abutting, overlapping or separated. The extension members 20 may berepositioned or removed as necessary during the surgical procedure. Uponcompletion of the procedure, the extension members 20 may be detachedand removed prior to removal of the retractor member 10, or may be leftin place and removed in combination with the retractor member 10.

It is contemplated that equivalents and substitutions to certainelements set forth above may be obvious to those skilled in the art, andthus the true scope and definition of the invention is to be as setforth in the following claims. It is further expressed that the aboveexamples and illustrations are meant to be representational rather thanlimiting in nature.

1. A retractor extension member for attachment to a retractor afterinsertion of the retractor into the body of a patient, the retractorextension member restricting tissue creep during surgical procedures,said retractor extension member comprising a main body and mountingmeans for removably mounting said extension member in a fixed,non-moving, position on a retractor having a distal end, said mountingmeans comprising a clip member disposed on said main body; whereby saidextension member is mountable on the retractor member such that thedistal end is received by said clip member and such that at least partof said main body extends beyond the retractor distal end.
 2. Theretractor extension member of claim 1, wherein said mounting meanscomprises a U-shaped clip member disposed on said main body of saidextension member.
 3. The retractor extension member of claim 1, whereinsaid mounting means comprises a J-shaped clip member disposed on saidmain body of said extension member.
 4. The retractor extension member ofclaim 1, wherein said mounting means comprises a slot disposed on saidmain body of said extension member and a U-shaped clip member positionedwithin said slot.
 5. The retractor extension member of claim 1, whereinsaid main body of said extension member is curved.
 6. The retractorextension member of claim 1, wherein said main body of said extensionmember is generally planar and is composed of a flexible material. 7.The retractor extension member of claim 1, further comprising toolconnector means for temporarily connecting said extension member to anapplicator tool.
 8. The retractor extension member of claim 7, whereinsaid tool connector means comprises an aperture disposed in saidextension member.
 9. The retractor extension member of claim 7, whereinsaid tool connector means comprises a projection.
 10. The retractorextension member of claim 1, further comprising teeth.
 11. The retractorextension member of claim 1, further comprising a curved lip.
 12. Theretractor extension member of claim 1, further comprising lateral wingsextending from said main body.
 13. The retractor extension member ofclaim 1, wherein said main body is composed of a relatively rigidcentral portion and a pair of relatively flexible lateral portions. 14.The combination of a retractor member and a plurality of extensionmembers; said retractor member comprising a distal end; each of saidextension members comprising a main body and mounting means forremovably mounting said extension member in a fixed, non-moving,position on said retractor member after said retractor has beenpositioned within a patient, said mounting means comprising a clipmember disposed on said extension member; whereby each of said extensionmembers is mountable on said retractor member such that said distal endis received by said clip member and such that at least part of said mainbody extends beyond said retractor distal end such that said extensionmember minimizes or precludes tissue creep at said distal end of saidretractor.
 15. The combination of claim 14, wherein said mounting meanscomprises a U-shaped clip member disposed on said main body of each saidextension member.
 16. The combination of claim 14, wherein said mountingmeans comprises a J-shaped clip member disposed on said main body ofeach said extension member.
 17. The combination of claim 14, whereinsaid mounting means comprises a slot disposed on said main body of saidextension member and a U-shaped clip member positioned within said slot.18. The combination of claim 14, wherein said main body of saidextension member is curved.
 19. The combination of claim 14, whereinsaid main body of said extension member is generally planar and iscomposed of a flexible material.
 20. The combination of claim 14, saidextension member further comprising tool connector means for temporarilyconnecting said extension member to an applicator tool.
 21. Thecombination of claim 20, wherein said tool connector means comprises atleast one aperture disposed in said extension member.
 22. Thecombination of claim 20, wherein said tool connector means comprises aprojection.
 23. The combination of claim 14, said extension memberfurther comprising teeth.
 24. The combination of claim 14, saidextension member further comprising a curved lip.
 25. The combination ofclaim 14, said extension member further comprising lateral wings. 26.The combination of claim 14, wherein said retractor member is tubular.27. The combination of claim 14, wherein said retractor member comprisesspreadable blades.
 28. The combination of claim 27, whereby each of saidextension members is also mountable laterally on said blades of saidretractor member such that at least part of said main body extendsbetween said blades.
 29. The combination of claim 27, said extensionmember further comprising lateral wings.
 30. The combination of claim14, wherein said extension members have varying configurations andsizes.
 31. The combination of claim 14, wherein said retractor isprovided with a plurality of grid apertures, at least some of said gridapertures being axially spaced such that not all said grid apertures areequidistant from said distal end.
 32. The retractor extension member ofclaim 14, wherein said main body is composed of a relatively rigidcentral portion and a pair of relatively flexible lateral portions. 33.The combination of claim 20, further comprising an applicator tool; saidapplicator tool comprising a pair of handles connected by pivot means toa pair of L-shaped arms, and extension member retention means disposedon said L-shaped arms to temporarily retain said extension members formounting to said retractor member.
 34. The combination of claim 20,wherein said tool connector means comprises at least one aperturedisposed in said extension member, and wherein said extension memberretention means comprise at least one pin that is received by said atleast one aperture.
 35. A method of preventing tissue creep at thedistal end of a retractor member during surgical procedures comprisingthe steps of: providing a retractor member having a distal end;providing at least one extension member comprising mounting means forremovably mounting said extension member in a fixed, non-moving,position on said retractor member, said mounting means comprising a clipmember disposed on said extension member, wherein said extension membercan be mounted at a plurality of locations on said retractor member;positioning said retractor in a patient; and mounting said at least oneextension member on said retractor member after said retractor has beenpositioned such that said distal end of said retractor member isreceived by said clip member and at least part of said extension memberextends beyond said distal end of said retractor member.
 36. The methodof claim 35, further comprising the step of providing plural extensionmembers and mounting additional extension members on said retractormember such that at least part of said additional extension membersextends beyond said distal end of said retractor member.
 37. The methodof claim 35, wherein said mounting step is performed by pulling saidclip member onto said distal end of said retractor member, whereby saidextension member can be positioned at any point on said distal end ofsaid retractor member.
 38. The method of claim 35, wherein saidretractor member comprises spreadable blades, and further mounting saidat least one extension member laterally on said blades of said retractormember such that at least part of said extension member extends betweensaid blades of said retractor member.
 39. The method of claim 35,wherein said mounting means comprises a slot disposed on said extensionmember and a U-clip member positioned within said slot, and wherein saidmounting step is performed by pulling said U-clip member onto saiddistal end of said retractor member, whereby said extension member canbe positioned at any point on said distal end of said retractor member.40. The method of claim 35 wherein said extension member is comprised ofa flexible material, wherein said mounting step comprises flexing saidextension member to match the curvature of said retractor member. 41.The method of claim 35, further comprising the steps of: providing anapplicator tool for handling said extension member during mounting onsaid retractor member; and wherein said mounting step comprises:temporarily mounting said extension member to said applicator tool;inserting said extension member and said applicator tool into saidretractor member; mounting said extension member on said retractormember; releasing said extension member from said applicator tool;removing said applicator tool from said retractor member.
 42. The methodof claim 41, further comprising the steps of: providing extension memberretention means on said applicator tool, said extension member retentionmeans comprising at least on pin member; providing tool connector meanson said extension member, said tool connector means comprising at leastone tool-receiving aperture; wherein said step of temporarily mountingsaid extension member to said applicator tool comprises inserting saidpin member into said tool-receiving aperture.
 43. The method of claim41, further comprising the steps of: providing a projection on saidextension member; wherein said step of temporarily mounting saidextension member to said applicator tool comprises grasping saidprojection with said applicator tool.
 44. The combination of a retractormember and a plurality of extension members; said retractor membercomprising a distal end and a plurality of apertures; each of saidextension members comprising a main body and mounting means forremovably mounting said extension member in a fixed, non-moving,position on said retractor member after said retractor has been insertedinto a patient, said mounting means comprising a post member disposed onsaid main body of said extension member; whereby each of said extensionmembers is mountable on said retractor member such that said post memberis received by one of said apertures and such that at least part of saidmain body extends beyond said retractor distal end.
 45. The retractorextension member of claim 44, wherein said main body of said extensionmember is curved.
 46. The retractor extension member of claim 44,wherein said main body of said extension member is generally planar andis composed of a flexible material.
 47. The retractor extension memberof claim 44, further comprising tool connector means for temporarilyconnecting said extension member to an applicator tool.
 48. Theretractor extension member of claim 47, wherein said tool connectormeans comprises an aperture disposed in said extension member.
 49. Theretractor extension member of claim 47, wherein said tool connectormeans comprises a projection.
 50. The retractor extension member ofclaim 44, further comprising teeth.
 51. The retractor extension memberof claim 44, further comprising a curved lip.
 52. The retractorextension member of claim 44, further comprising lateral wings.
 53. Afenestrated surgical retractor, said retractor comprising a main body, adistal end and a plurality of grid apertures, wherein at least some ofsaid grid apertures are axially spaced such that not all said gridapertures are equidistant from said distal end.
 54. The retractor ofclaim 53, wherein said grid apertures receive mounting clips attached tosurgical accessories, whereby said surgical accessories are mountable tothe interior of said retractor.
 55. The retractor of claim 54, whereinsaid grid apertures receive mounting clips attached to retractorextension members, wherein said extension members are mounted to theends or sides of said retractor.
 56. The retractor of claim 53, whereinsaid retractor is tubular.
 57. The retractor of claim 53, wherein saidretractor is a spreadable blade retractor.
 59. The retractor of claim53, in combination with surgical accessories, said surgical accessoriescomprising mounting clips, wherein said grid apertures receive saidmounting clips such that said surgical accessories are mounted withinthe interior of said retractor.
 60. The combination of claim 59, furthercomprising retractor extension members comprising mounting clips,wherein said extension members are mounted to the ends or sides of saidretractor.
 61. The retractor of claim 59, wherein said retractor istubular.
 62. The retractor of claim 59, wherein said retractor is aspreadable blade retractor.
 63. The combination of a retractor memberand a plurality of extension members; said retractor member comprising adistal end; each of said extension members comprising a main body andmounting means for removably mounting said extension member in a fixedposition on said retractor member, said mounting means comprising amechanical interlocking member disposed on said main body of saidextension member; whereby each of said extension members is mountable onsaid retractor member such that said mechanical interlocking member isretained upon said retractor member and such that at least part of saidmain body extends beyond said retractor distal end.
 64. The combinationof claim 63, wherein said retractor member is tubular.
 65. Thecombination of claim 63, wherein said retractor member is a spreadableblade retractor comprising blades.
 66. The combination of claim 63,wherein some of said extension members are mountable on said retractormember such that at least part of said main body extends laterallybeyond said blades.
 67. The combination of a tubular retractor memberand a plurality of extension members; said retractor member comprising adistal end; each of said extension members comprising a main body andmounting means for removably mounting said extension member in a fixed,non-moving, position on said retractor member after said retractor hasbeen positioned within a patient, said mounting means comprising aslotted annular collar member; whereby each of said extension members ismountable on said retractor member such that said collar member ispositioned at or near said distal end such that at least part of saidmain body extends beyond said retractor distal end such that saidextension member minimizes or precludes tissue creep at said distal endof said retractor.
 68. The combination of claim 67, wherein saidextension members are retained within said retractor member byfrictional forces.
 69. The combination of claim 67, wherein saidextension members are retained within said retractor member by biasingforces.